The new photovoltaic compound Ag2ZnSn(S,Se)4 (“AZTSSe”) has many promising material properties. AZTSSe has a lower defect density than the compound it is based on, Cu2ZnSn(S,Se)4 (“CZTSSe”). See, for example, U.S. patent application Ser. No. 14/936,131 by Gershon et al., entitled “Photovoltaic Device Based on Ag2ZnSn(S,Se)4 Absorber” (hereinafter “U.S. patent application Ser. No. 14/936,131”).
Grain size affects energy conversion efficiency of absorber materials, with a larger grain size generally resulting in a greater efficiency. Therefore, techniques for controlling the grain size in AZTSSe absorber materials would be desirable.